1. Technical Field
The present invention relates to a device for buffering molded parts in a beverage filling plant, preferably for buffering container closures for a capper in a beverage filling plant.
2. Related Art
It is known to feed container closures, and in particular closure caps for containers, in a beverage filling plant to the actual capper by means of various transport devices. In this, it is known to feed the container closures, for example plastic screw caps for closing PET bottles, via guide chutes to the capper. Differences in elevation between different components of the plant can be overcome by means of, for example, air conveyors, belt conveyors or waterfall conveyors.
Because interruptions can occur in the production process in a beverage filling plant, various storage systems are disposed between the sorter, in which the container closures are sorted into the correct orientation, and the actual capper. These buffer devices can be provided, for example, by elongated systems of channels which have an appropriate holding capacity for the container closures. The appropriate buffering capacity for the container closures that have been presorted into the correct orientation is thus provided by means of configurations which have long transport paths. Accordingly, if a disruption then occurs in the feeding of the container closures to the sorter, or a disruption occurs inside the sorter, the production process in the beverage filling plant can continue to operate, since an adequately large quantity of container closures are still available via the buffer capacity of such a system.
However, the space requirements of such elongated transport paths and/or long systems of channels are a disadvantage. Closure buffers which provide more compact buffering capacities are therefore known. For example, from DE 41 42 785 A1 a device for use with a closure magazine for introducing crown caps or similar devices into a closure channel is known, which has a substantially vertically disposed buffering capacity. The container closures are guided via a narrowing at the output to the subsequent system of channels. The disadvantage of such a buffer system is that the loss of elevation required by the gravity feed makes it necessary to raise the container closures again, or else the container closures must be raised from the outset to a greater elevation. A further disadvantage is that the weight of all of the closures exerts a corresponding downwards pressure, with the result that large forces can arise at the output due to the pressure from above, and this can result in the deformation of the container closures. Accordingly, there is relatively high wear on the container closures caused by the high pressure they exert on each other due to the design of such a buffer device which operates on a gravity principle.
The revolver-like buffering system described in EP 1 801 066 A2 also uses the difference in elevation to empty its revolving shaft. However, first, this results in a complex design of the buffer, with relatively high pressure of the container closures on each other again resulting at the output due to the height of the stack of container closures, and second, the loss of elevation mentioned above again occurs, and this must be compensated for either before or after the revolver-like buffering system.
A loss of elevation also takes place in the buffering solutions known from DE 698 00 834 T2 and EP 1 803 681 A2, which must be compensated for either before or after each of these buffers in order to reach the elevation of the actual processing in the capper.